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Where and When Did the Symbols "+" and "–" Originate?

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Re: Where and When Did the Symbols "+" and "–" Originate?

#31

Post by yaddayadda »

The next logical question is, "Where did × and ÷ originate?" From there, I've always wondered how multiplication migrated from "×" to "∗"? And recently, I've wondered if we will migrate "-" to something else? (This last derives from having to annotate a range of numbers including positive and negative. When "-" is used for both range and negative, it causes confusion.)

p.s. I tried to post this to the original poster's blog, but was told "...your comment seems a bit spammy." Really? I'd say their blogger spam settings a more than a bit off.

Re: Where and When Did the Symbols "+" and "–" Originate?

#32

Post by qompiler »

Chinese write it as 加, if you start making the strokes you get a + in the upper left. Consider this is over 6000 years old, probably the origin. My theory.

Edit (more evidence): "The plus symbol as an abbreviation for the Latin et, though appearing with the downward stroke not quite vertical, was found in a manuscript dated 1417 (Cajori)."

There is an assumption here that it's an abbreviation for the Latin et. But the downward stroke can be seen in the Chinese word.

Re: Where and When Did the Symbols "+" and "–" Originate?

#33

Post by recuter »

adamnemecek wrote: post #2

This always amazed me: "A Jewish tradition that dates from at least the 19th century is to write plus using a symbol like an inverted T. This practice was adopted into Israeli schools (this practice goes back to at least the 1940s)[11] and is still commonplace today in elementary schools (including secular schools) but in fewer secondary schools.[12] It is also used occasionally in books by religious authors, but mos…

I have an uncomfortable memory of my 1st grade teacher showing this to us and me refusing to go along with what I insisted was an irrational superstition. I didn't understand the context or what her old age meant.

Similarly, I was shocked as a kid when I visited the US and saw apartment buildings skip the 13th floor numbering.

People are weird.

Re: Where and When Did the Symbols "+" and "–" Originate?

#34

Post by ghc »

recuter wrote: post #33
adamnemecek wrote: post #2

This always amazed me: "A Jewish tradition that dates from at least the 19th century is to write plus using a symbol like an inverted T. This practice was adopted into Israeli schools (this practice goes back to at least the 1940s)[11] and is still commonplace today in elementary schools (including secular schools) but in fewer secondary schools.[12] It is also used occasionally in books by religious authors, but mos…

I have an uncomfortable memory of my 1st grade teacher showing this to us and me refusing to go along with what I insisted was an irrational superstition. I didn't understand the context or what her old age meant. Similarly, I was shocked as a kid when I visited the US and saw apartment buildings skip the 13th floor numbering. People are weird.

Similarly, in Japan one pronunciation of 4 is also the word for death, so it's frequently omitted.

Re: Where and When Did the Symbols "+" and "–" Originate?

#35

Post by rootbear »

pavlov wrote: post #5

What fascinates me most about this story is how it illustrates what a young race we humans are intellectually. If we ever want to be anything more than warring tribes, we must learn to accumulate knowledge together. Universal symbols for addition and substraction are the first small step on that very long road, yet it's only been a few hundred years since we took that step. On the scale of the universe, we are like a…

And we're still using '*' for multiplication in our programming languages instead of '×' because using anything other than ASCII for programming is just too hard, or too weird, or whatever.

Re: Where and When Did the Symbols "+" and "–" Originate?

#36

Post by manish_gill »

yaddayadda wrote: post #31

The next logical question is, "Where did × and ÷ originate?" From there, I've always wondered how multiplication migrated from "×" to "∗"? And recently, I've wondered if we will migrate "-" to something else? (This last derives from having to annotate a range of numbers including positive and negative. When "-" is used for both range and negative, it causes confusion.) p.s. I tried to post this to the original poster…

I always thought the * was used for multiplication to avoid confusing × with the English alphabet X. We can usually distinguish them while writing equations on paper(I write x in a cursive, for example).

Re: Where and When Did the Symbols "+" and "–" Originate?

#37

Post by yaix »

> Overall, what is perhaps most impressive in this story is the fact that symbols which first appeared in print only about five hundred years ago have become part of what is perhaps the most universal “language.”

They appeared just at the right time to be carried around the world by conquista and colonialism. Same goes for time notation, etc.

Re: Where and When Did the Symbols "+" and "–" Originate?

#38

Post by zapdrive »

yread wrote: post #30

We discussed this article in the office and among other things we found that even today the notation for division (when calculating it by hand) varies wildly: In Czech Republic we would write 453: 12 = 37.75 In Netherlands: 12/453\37.75 In Russia: 453 | 12 | 37.75 all of them are listed on Wikipedia http://en.wikipedia.org/wiki/Long_division

In India its usually written: 500 ÷ 4 = 125. Its not a + sign, it a bar stuck between a :

Re: Where and When Did the Symbols "+" and "–" Originate?

#39

Post by rmccue »

mich41 wrote: post #19
abrahamsen wrote: post #13

Kind of weird that no consensus have emerged for multiplication (·, ×, *, or horizontal juxtaposition) or division (÷, /, or vertical juxtaposition with horizontal line between) yet.

Everybody uses juxtaposition for multiplication (or dot when some separation is required) and horizontal line for division. * and / are poor man's substitutes when all you have is ASCII. × is used for vector products, Cartesian products and products of algebraic structures in general. The only place I've ever seen × or ÷ being used in arithmetics was primary school. No idea why they use them.

÷ is the symbol for division since it symbolises a fraction, with the two dots taking the place of the numbers. I'd say this is why, as some people have noted, : can also be used for division in some contexts: it represents a ratio, which is again just a fraction.

Re: Where and When Did the Symbols "+" and "–" Originate?

#40

Post by rmccue »

zapdrive wrote: post #38
yread wrote: post #30

We discussed this article in the office and among other things we found that even today the notation for division (when calculating it by hand) varies wildly: In Czech Republic we would write 453: 12 = 37.75 In Netherlands: 12/453\37.75 In Russia: 453 | 12 | 37.75 all of them are listed on Wikipedia http://en.wikipedia.org/wiki/Long_division

In India its usually written: 500 ÷ 4 = 125. Its not a + sign, it a bar stuck between a :

That's normal division, which is a notation. The GP is talking about long division, which is a technique used to divide large numbers.

The symbol in Australia (and I'd say most of the English speaking world) looks like a long square root sign with a curved vertical part:

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